1. Technical Field
The invention relates to techniques for stabilizing a result of detecting an image.
2. Related Art
There has been conventionally known an image forming apparatus for forming a test image (that is, detection image or image-to-be-detected) and detecting this test image to obtain information relating to image formation. For example, an image forming apparatus disclosed in Japanese Patent No. 2642351 forms test images (“detection pattern” of Japanese Patent No. 2642351) for a plurality of colors and obtains color misregistration information necessary for color image formation. Specifically, the apparatus disclosed in Japanese Patent No. 2642351 forms a color image by superimposing toner images of a plurality of colors on a transfer medium. In order to satisfactorily form this color image, test images are formed for the respective colors. The test images are detected by optical sensors and the positions of the test images are obtained from the detection results. The color misregistration information can be obtained from the thus obtained positions of the test images of the respective colors. In this way, the test images are formed and the information relating to image formation is obtained from the detection results on the test images in the apparatus disclosed in Japanese Patent No. 2642351.